Junction-box for electrical conductors.



-BE AVALABLE COP rum-mp DEC. 1

' E. '1. unnnfiFIELD. l 5 5w 5 JUNCTION BOX FOR ELECTRICAL UONDUCTORS.

APPLICATION TILE]? JUNE 21, 1904.

fig-4 r INVENTOR BEST AVAlLABLE'COP UNITED STATES PATENT OFFICE.

JUNCTION-BOX FOR ELECTRICAL OONDUOTORS.

7 Specification of Letters Patent.

Patented Dec. 12, 1905.

- Application filed June 21, 1904. Serial No. 213,49L

To all whom it may concern.-

Be it known that I, EDWIN T. GREENFIELD, a citizen of the United States, residing at My invention is directed particularly to im-' provements in junction-boxes like those dis closed in, my prior United States Patents No. 642,521, granted January 30, 1900; No. 651,484, granted June 12, 1900, and No. 665,677, granted January 8, 1901; and it has for its objects, first, to provide means for effectually closing such of the inlet-openings as are not needed when thebox is put in place 5 second, to provide means whereby the inleading ends of the armored conductors or conduits may be effectually clamped or held in place within the inner surface of the box, the arrangement being such that the same means which is utilized to effect the closure of such of the inlet-o enings as are not in use is also utilized to e eat the clamping action upon the inleading ends of the armored conductors or conduits.

For a full and clear understanding of my invention such as will enable others skilledin the art to construct and use the same reference is had to the accompanying drawings, in which Figure 1 is a plan view of a junction-box with my improvement applied thereto, illustrating also two inleading flexible armored conductors secured thereto. Fig. 2 is a sectional view taken through Fig. 1 on the line A B and as seen looking thereat from the left toward the right in the direction of the arrows, the armored conductors being shown in side elevational view in dotted lines. Fig. 3

' is a sectional view taken through Fig. 1 on the line C D and as seen looking thereat from the bottom toward the top of the drawings in the direction of the arrows, the armored conductors being shown in end elevational view. Fig. 4 is a detail side elevational view of one of the shutters or disks which close the unused inlets, and Fig. 5 is a perspective view of the means for holding the shutters or closing means and also for clamping the ends of the inleading armored conductors or conduits.

Referring now to the drawings in detail, in all of which like numerals of reference represent like parts wherever used, 1 represents a junction-box of well-known form, provided with a series of inlets 2 2 2 2 for receiving the incoming ends of armored conductors or conduits 3 3, 4 4 being ears or lugs provided with screw-holes for ,securin the lid or cover of the box, (not shown,) sai box being provided with the usuals'crew-holes in its bottom for securing it by screws directly to the ceiling or side wall.

5 is a clamping-ring the exterior diameter of which is such as to adapt it to fit snugly within the inner concentric surface or :wall of the box, said ring being provided with downwardly-extending locking lugs or ears 9 9 9, of interior curvilinear form, on their under surfaces, as shown at 11 11, and. having interior grooves 10 10, adapted to receive shutters or disks 12, of curvilinear form, at their upper ends, the arrangement being such that when these disks are in position and the clamping-rin secured within the box each of said disks wi 1 close a corresponding inletopening 2. a

6 6 are screw-holes passing through ears or lugs on'the interior of the clamping-ring 1 and ada ted to receive screws 8 8, the son threade ends of which may be secured i tegral lugs or ears 7 7 in the bottom in .ne box.

In using the box it is first secured in place upon the ceiling or a ainst the wall by screws passing through the Fottom, as shown in Fig. 1, and such of the shutters or disks 12 are removed by withdrawing them from the grooves 10 10 of the clamping-ring 5 as may be necessary to accommodate the desired number of inleading armored conductors of conduits 3 3, two being shown in the drawings. These conductors or conduits are inserted as shown in Fi s. 1 and 2, and the cla1nping-ring inserte Within the box so that the downwardlyextending locking-lugs 9, with their curvilinear interior surfaces 11, will rest snugly upon the armor of the conductors or conduits, the shutters, or disks 12 remaining in corresponding downwardly-extending BEST AVAILABLE COP which perform the double function-of clamp-' ing the inleading ends of the armored conductors and closing the unused openings, are for all practical purposes a single piece. Such a structural arrangement avoids or overcomes the objectionable feature of breakage in the putting of the box in position, as often occurs with that form of junction-box disclosed in my prior patent, No. 642,521, in which the closing-disks are integral with the box, such breakage occurring by reason either of imperfect casting or careless manipu- 'lation in breaking down or out the closingdisks to the inlets. It also avoids the necessity of providing a separate set-screw or clamping device for each inleading armored conductor or conduit and sim lifies the construction of the conduit-box itself in that it avoids the necessity of providing necks for supporting such set-screws.

I do not limit my invention to the especial details of construction disclosed in the accompanying drawings, as the same might be departed from and stillcome within thescope of my claims hereinafter made. Nor do I limit the structural arrangement to a circular arm of box, as obviously the same might be rectangular or of any preferred shape, the

iping means 5 being of corresponding ntric conformation and adapted to rest upon the inleading ends of all of the armored conductors or conduits and to firmly clamp or hold the same from withdrawal therefrom.

I am aware that a two-part junction-box has heretofore been devised in which there are cut in the side walls of each part of the box semicircular openings provided with concentric semicircular grooves for receiving circular disks in such manner as to close such of the openings as it is not designed to use in connection with house-conduits, the same being held together by screws assing through the lid or up er portion of t e box and into the side wal s of the lower portion thereof, but without any binding action whatever upon the ends of the conduits or cables. My invention differs from this in that I provide us independent of the box for performe double function of holding the detachable disks and simultaneously gripping or -wall of the box and additional means for causing the-same to act simultaneously upon all'of the ends of the inleading armored conductors or conduits.

2. A junction-box provided with a series of inlets; a series of shutters -or disks one for each inlet, and clamping means concentric withthe inner surface or wall of the-box for holding the shutters or disks in such position as to close the inlets.

3. A junction-box provided with a series of inlets and a series of shutters or disks for closing said inlets, said shutters or disks being supported by a ring concentric with the inner surface or wall of the box and detachable therefrom.

4. A j unction-box provided with a series of inlets; in combination with a clamping-ring concentric with the inner surface or wall of said box and a series of shutters or disks carried by said clamping-ring; together with means for securing the clamping-ring to the bottom of the box and in such position as to hold the inleading ends of corresponding armored conductors and to maintain the shutters or disks in such position as to close the unused inlets.

5. A junction-box provided with a clamping-ring having curvilinear lugs adapted to fit about the ends of inleading armored conductors, and means for securing detachable shutters or disks opposite the unused inlets; together with means for securing said ring to the bottom of the box.

6. A j unction-box provided with a plurality of inlets for the reception of the ends of inleading conductors or conduits; in combination with removable shutters for closing the same; together with means common to i BEST AVAILABLE COP i .LgS in the side walls of the box proper; in combination with removable shutters and means Within the box for securing the shutters in front of the openings, the shutters, when in position, resting upon the bottom of the box.

9. A junction-box having circular openings in its side walls and a series of detachable shutters for closing the same; in combination with means located wholly within the box for securing the shutters in place, said ters.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

EDWIN T. GREENFIELD.

Witnesses:

O. E. MAoSoRLEY, C. J. KINTN'ER; 

